Young sons getting space for convenience (6,4,4)

I believe the answer is:

little boys room

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'convenience' is the definition.
I don't know anything about this answer so I can't tell whether this works.

'young sons getting space' is the wordplay.
'young' becomes 'little' (similar in meaning).
'sons getting' becomes 'boys' (I can't justify this - if you can you should give a lot more credence to this answer).
'space' becomes 'room' (enough space or room to do something).
'little'+'boys'+'room'='LITTLE BOYS ROOM'

'for' is the link.

Can you help me to learn more?

(Another definition for little boys room that I've seen is " toilet".)

I've seen this clue in The Daily Express.

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